Benzil, molecular crystal

Decarbonylation and Decarboxylation - The photochemical reactions between carboxylic acids such as formic and trifluoroacetic acid and silica surfaces have been studied. The irradiation of diphenylacetic acid in acetonitrile with acridine results in the decarboxylation and the formation of the adduct (102). When the two achiral compounds, acridine and diphenylacetic acid, are cocrystallized a chiral two component molecular crystal is obtained in which the components are present in a 1 1 ratio. Both (—)- and (+)- crystals can be obtained. This crystalline material is photochemically reactive and irradiation brings about decarboxylation and formation of the adduct (102) with an ee of 35%. This compound is accompanied by a low yield of (103) which is formed exclusively on irradiation of the reactants in acetonitrile solution.Photochemical decarboxylation can be brought about by the irradiation of benzilate (104)/ methyl viologen pairs. ... 

Meyerhoeffer, A. and Carlstroem, D. 1969. Crystal and molecular structure of quinucUdinyl benzilate hydrobromide. Acta Crystallographica, B, 25 1119-1126. 

The a-diketone precursors used to prepare the dithiolene complexes discussed above can be used for the preparation of other potential ligands such as dioximes. Such ligands are directly obtained by the reaction of the corresponding benzil species with hydroxylamine chloride. Dioximato complexes with cf metals crystallize in columnar stacks with the formation of a chain of metals orthogonal to the molecular planes, and as such are potentially interesting candidates for the design of discotic systems with low-dimensional semiconducting properties. Ohta et al. reported a... 

CHANGE OF MOLECULAR GEOMETRY OF BENZIL MOLECULE IN STILBENE SINGLE CRYSTAL. 

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